The invention relates to an orbital sander and more particularly to an orbital sander having a sanding plate capable of being set into reciprocating motion by an eccentric drive element driven either directly or indirectly by the armature shaft of a drive motor.
Conventional orbital sanders of this type typically have no reduction gear between the armature shaft of the drive motor and the drive shaft of the sanding plate, so that the armature shaft and drive shaft are identical.
However, orbital sanders of this generic type are also known in which the rpm of the drive motor is stepped down by means of a conventional gear and the oscillation frequency of the sanding plate is correspondingly reduced. The gears used for this purpose occupy a not inconsiderable amount of installation space, however, and they are also expensive.
It is an object of the invention to provide a gear design that with minimum installation space and at minimal cost enables a reduction, selectable within a relatively wide range, of the rpm of the armature shaft of the drive motor.